Datasheet AD8220 (Analog Devices)

JFET Input Instrumentation Amplifier with Rail-to-Rail Output in MSOP Package AD8220 FEATURES PIN CONFIGURATION Low input currents AD8220 10 pA maximum input bias current (B grade) –IN 1 8 +VS 0.6 pA maximum input offset current (B grade) RG 2 7 VOUT High CMRR RG 3 6 REF 100 dB CMRR (minimum), G = 10 (B grade) +IN 4 5 –VS
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80 dB CMRR (minimum) to 5 kHz, G = 1 (B grade) TOP VIEW
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(Not to Scale)
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Excellent ac specifications and low power
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1.5 MHz bandwidth (G = 1)
Figure 1.
14 nV/√Hz input noise (1 kHz) Slew rate: 2 V/μs 750 μA quiescent supply current (maximum) 10n Versatile MSOP package A) 1n ( Rail-to-rail output I NT BIAS Input voltage range to below negative supply rail 100p 4 kV ESD protection CURRE 4.5 V to 36 V single supply AS 10p BI ±2.25 V to ±18 V dual supply UT IOS 1p Gain set with single resistor (G = 1 to 1000) INP Qualified for automotive applications 0.1p
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APPLICATIONS
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–50 –25 0 25 50 75 100 125 150 Medical instrumentation TEMPERATURE (°C) Precision data acquisition
Figure 2. Input Bias Current and Offset Current vs. Temperature
Transducer interfaces GENERAL DESCRIPTION
The AD8220 is the first single-supply, JFET input instrumentation Gain is set from 1 to 1000 with a single resistor. Increasing the amplifier available in an MSOP package. Designed to meet the gain increases the common-mode rejection. Measurements that needs of high performance, portable instrumentation, the AD8220 need higher CMRR when reading small signals benefit when has a minimum common-mode rejection ratio (CMRR) of 86 dB the AD8220 is set for large gains. at dc and a minimum CMRR of 80 dB at 5 kHz for G = 1. Maxi- A reference pin allows the user to offset the output voltage. This mum input bias current is 10 pA and typically remains below feature is useful when interfacing with analog-to-digital converters. 300 pA over the entire industrial temperature range. Despite the JFET inputs, the AD8220 typically has a noise corner of only 10 Hz. The AD8220 is available in an MSOP that takes roughly half the board area of an SOIC. Performance for the A and B grade is With the proliferation of mixed-signal processing, the number specified over the industrial temperature range of −40°C to +85°C, of power supplies required in each system has grown. The AD8220 and the W grade is specified over the automotive temperature is designed to alleviate this problem. The AD8220 can operate range of −40°C to +125°C. on a ±18 V dual supply, as well as on a single +5 V supply. Its rail-to-rail output stage maximizes dynamic range on the low voltage supplies common in portable applications. Its ability to run on a single 5 V supply eliminates the need to use higher voltage, dual supplies. The AD8220 draws a maximum of 750 μA of quiescent current, making it ideal for battery powered devices.
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Document Outline Features Applications Pin Configuration General Description Revision History Specifications Absolute Maximum Ratings ESD Caution Pin Configuration and Function Descriptions Typical Performance Characteristics Theory of Operation Gain Selection Layout Common-Mode Rejection Ratio (CMRR) Grounding Reference Terminal Power Supply Regulation and Bypassing Input Bias Current Return Path Input Protection RF Interference Common-Mode Input Voltage Range Driving an ADC Applications Information AC-Coupled Instrumentation Amplifier Differential Output Electrocardiogram Signal Conditioning Outline Dimensions Ordering Guide Automotive Products